staging: dgnc: convert to wait_event_interruptible_timeout

This patch makes use of wait_event_interruptible_timeout to achieve
timeout functionality.This is a TODO mentiond in the comment which is also
removed.It also aligns with what the function is supposed to do as in the
comments.
Signed-off-by: Hari Prasath Gujulan Elango <hgujulan@visteon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/dgnc/dgnc_neo.c

@@ -1306,10 +1306,10 @@ static int neo_drain(struct tty_struct *tty, uint seconds)
 	/*
 	 * Go to sleep waiting for the tty layer to wake me back up when
 	 * the empty flag goes away.
-	 *
-	 * NOTE: TODO: Do something with time passed in.
 	 */
-	rc = wait_event_interruptible(un->un_flags_wait, ((un->un_flags & UN_EMPTY) == 0));
+	rc = wait_event_interruptible_timeout(un->un_flags_wait,
+					      ((un->un_flags & UN_EMPTY) == 0),
+					      msecs_to_jiffies(seconds * 1000));
 
 	/* If ret is non-zero, user ctrl-c'ed us */
 	return rc;